1. Field of the Description
The present invention relates, in general, to small passenger boats (e.g., boats for carrying 1 to 50 or more passengers) and to equipment that facilitates the loading and unloading of passengers from such boats when they are positioned near a dock, and, more particularly, to methods and systems for stabilizing a passenger boat to allow safe loading and unloading of passengers while the boat is adjacent to a dock (e.g., any platform positioned along a body of water).
2. Relevant Background
There are numerous applications where relatively small passenger boats are loaded and unloaded from docks, and this loading and unloading may be performed numerous times each day. For example, amusement parks often feature a number of water rides that may be designed to provide one or more passenger boats floating along a stream of water in a channel and, in some cases, each of the boats is guided from underneath using a track, which is provided at the bottom of the channel. These water rides may be gentle rides, such as rides used to provide a show or an outdoor adventure, or may include thrill portions where the boats travel quickly through rapids. In each of these settings, the boat typically is guided in a manner that allows the boat to float in the water with the boat and its passengers experiencing pitch and other common boat-related or floating dynamics (such as roll or yaw).
Passenger safety has represented one of the main challenges for designers of water rides. Safety is of particular concern for passenger boats when the passengers are loading the boat from a dock and also when they later unload the boat and have to step from the boat onto the dock. For example, a passenger boat may have its movements generally guided by a connection to a track on a channel bottom. However, even when tied up to a dock, the boat has some freedom of movement as it can bob up and down in the water and roll side to side so that the ride more fully simulates a true boating experience.
More specifically, amusement parks often use self-propelled and free-floating boats in their excursion and other rides. Small, self-propelled, free-floating boats with relatively large passenger capacities are, in general, dynamically unstable in roll and pitch motion during the load and unload processes. As passengers embark and disembark, they must step into or out of the boat from or onto an adjacent dock (e.g., the upper, planar surface of a dock or platform). Since their first or last point of support is usually the side of the boat or a top step inside of the boat, the stepping into and out of action by the passengers induces a transient dynamic roll or pitch moment in the boat as a concentrated load is placed on the outer edges of the boat. In other words, the boat sinks into the water as a person steps onto it and rises as the passenger steps out of the boat.
There is usually a clearance gap or space between the side of the boat and outer edge (or boat-facing side) of the dock, and the size of this gap or space that the passenger has to step over to safely reach the dock changes as the boat moves in response to passenger movement and also in response to water movement. Depending on the load in the boat, the height of the final step onto the dock (or off of the dock into the boat) will also change with the passenger movements and the resulting roll and pitch moments. The passenger may find the motion between the boat and dock disorienting or otherwise may have difficulty adjusting to the changing gap and/or height. This can create a safety hazard for the boat passengers, and operators of water rides continue to be concerned that passengers may experience injuries due to falls either into the boat, into the gap and water, or onto the dock.
Presently, operators of water rides attempt to position the guiding track (if there is one) so as to place the boat very near to the dock, and safety is improved by fastening the boat to the dock during loading and unloading. However, the boat typically can still move, which causes the gap and height of the boat to vary a significant amount during loading and unloading as passengers step on or near the edge of the boat and then off the boat onto the dock (or vice versa for loading). Hence, there remains a need for systems and methods for stabilizing small passenger boats to eliminate or at least better control the amount of dynamic movement (e.g., dynamic pitch) the boat experiences during loading and unloading.
Such a stabilizing system or assembly may be adapted for rapidly stabilizing the boat (or its hull) and then releasing the boat to allow the boat to move away from the dock, and such speed may be even more desirable in amusement parks interested in high passenger throughput. However, the stabilizing system may be useful in nearly any application in which a boat is positioned along a dock for loading and unloading where passengers are expected to step onto or from the boat and where the varying step height (relative height of the dock compared to the boat) and clearance gap may be considered a potential hazard.